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Am găsit aria Δ[tex]_{ABC} [/tex] : [tex] \frac{AB ori AC ori sinA}{2} [/tex] = [tex] \frac{6 ori 10 ori sinA}{2} [/tex] => sinA = 60/2 = 30°

Am nevoie de ajutor mai departe.


Am Găsit Aria ΔtexABC Tex Tex FracAB Ori AC Ori SinA2 Tex Tex Frac6 Ori 10 Ori SinA2 Tex Gt SinA 602 30 Am Nevoie De Ajutor Mai Departe class=

Răspuns :

[tex] \frac{6*10*sinA}{2}=15 \sqrt{3 } \\ \frac{60sinA}{2} =15 \sqrt{3} \\ 30sinA =15 \sqrt{3};sinA= \frac{ \sqrt{3} }{2} \\ cosA= \sqrt{1-( \frac{ \sqrt{3} }{2})^2 } = \sqrt{ \frac{1}{4} }= \frac{1}{2} \\ BC^{2}= AB^{2}+ AC^{2}-2AB*AC*cosA \\ BC^{2}=36+100-2*6*10* \frac{1}{2} \\ BC^2=136-60=76 \\ BC= \sqrt{76} cm[/tex]